firmosses

''Huperzia'' is a genus of lycophyte plants, sometimes known as the firmosses or fir clubmosses; the ''Flora of North America'' calls them gemma fir-mosses. This genus was originally included in the related genus ''Lycopodium'', from which it differs in having undifferentiated sporangial leaves, and the sporangia not formed into apical cones. The common name ''firmoss'', used for some of the north temperate species, refers to their superficial resemblance to branches of fir (''Abies''), a conifer. , two very different circumscriptions of the genus were in use. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), ''Huperzia'' is one of three genera in the subfamily Huperzioideae of the family Lycopodiaceae. Most species in the subfamily are placed in the genus ''Phlegmariurus''. ''Huperzia'' is left with about 25 species, although not all have been formally transferred to other genera. Other sources recognize only ''Huperzia'', which then has about 340 species.

Morphology

The sporophytes of this genus have unbranched shoots that are generally upright and round in cross section. Horizontal stems are absent. The leaves are not borne in distinct ranks, and are usually somewhat lanceolate in shape. In some species, they vary in size according to the season in which they grow. Branchlets bearing gemmae – bud-like structures by which the plant reproduces asexually – occur among the leaves. The gemmae are triangular, with eight leaves in a constant pattern: four flattened into a plane and two large lateral leaves. The sporangia are kidney-shaped (reniform), occurring at the base of a leaf that is either unmodified or reduced. The roots are produced near the apex of shoots, and migrate downwards inside the cortex of the stem to emerge at soil level. The unbranched gametophytes are not photosynthetic, but rather subterranean and mycorrhizal.

The ''Flora of North America'' distinguishes ''Huperzia'' from the epiphytic tropical genus ''Phlegmariurus'' on the basis of differences such as the former's complex and specialized shoots, the gemmae and the branchlets on which they are borne, and the unbranched gametophytes.

Taxonomy

The genus ''Huperzia'' was created by Johann Jakob Bernhardi in 1801. Bernhardi separated ''Huperzia'' from ''Lycopodium''. The type species is ''Lycopodium selago'' which became '' Huperzia selago''.

In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), ''Huperzia'' is placed in the subfamily Huperzioideae of the family Lycopodiaceae. A phylogenetic study in 2016, employing both molecular and morphological data, concluded that either a one-genus or a three-genus division of the subfamily produced monophyletic taxa. The authors preferred the three-genus division, recognizing ''Huperzia'', ''Phlegmariurus'' and ''Phylloglossum''. Their preferred hypothesis for the relationships of the three genera was:

The majority of the species formerly placed in a broadly defined ''Huperzia'' belong in ''Phlegmariurus''. Earlier, the ''Flora of North America'' had also separated ''Huperzia'' from ''Phegmariurus''. However, ''Phlegmariurus'' is difficult to separate morphologically, and others have preferred the one-genus division of the subfamily.

Species

The PPG I classification stated there were 25 species in the genus ''Huperzia''. , ''World Ferns'' listed 56 species, noting that "many species still need transfer into other split genera".

*'' Huperzia appalachiana'' Beitel & Mickel
*'' Huperzia archboldiana'' (Nessel) Holub
*'' Huperzia arunachalensis'' (D.D.Pant & P.S.Pandey) Fraser-Jenk.
*'' Huperzia asiatica'' (Ching) N.Shrestha & X.C.Zhang
*'' Huperzia australiana'' (Herter) Holub
*'' Huperzia beccarii'' (Alderw.) Holub
*'' Huperzia bucahwangensis'' Ching
*'' Huperzia campestris'' (Alderw.) Holub
*'' Huperzia chinensis'' (Christ) Ching
*'' Huperzia chishuiensis'' X.Y.Wang & P.S.Wang
*'' Huperzia continentalis'' Testo, A.Haines & A.V.Gilman
*'' Huperzia crispata'' (Ching) Ching
*'' Huperzia emeiensis'' (Ching & H.S.Kung) Ching & H.S.Kung
*'' Huperzia erubescens'' (Brack.) Holub
*'' Huperzia everettii'' (Herter) Holub
*'' Huperzia fuegiana'' (Roiv.) Holub
*'' Huperzia gedeana'' (Alderw.) Holub
*'' Huperzia goliathensis'' (Alderw.) Holub
*'' Huperzia haleakalae'' (Brack.) Holub
*'' Huperzia herteriana'' (Kümmerle) T.Sen & U.Sen
*'' Huperzia javanica'' (Sw.) Fraser-Jenk.
*'' Huperzia jejuensis'' B.Y.Sun & J.Lim
*'' Huperzia kangdingensis'' (Ching) Ching
*'' Huperzia kunmingensis'' Ching
*'' Huperzia laipoensis'' Ching
*'' Huperzia lajouensis'' Ching
*'' Huperzia leishanensis'' X.Y.Wang
*'' Huperzia liangshanica'' (H.S.Kung) Ching & H.S.Kung
*'' Huperzia lucidula'' (Michx.) Trevis.
*'' Huperzia medogensis'' Ching & Y.X.Lin
*'' Huperzia meghalaica'' Fraser-Jenk.
*'' Huperzia miniata'' (Spring) Trevis.
*'' Huperzia minima'' (Herter) Holub
*'' Huperzia miyoshiana'' (Makino) Ching
*'' Huperzia muscicola'' W.M.Chu
*'' Huperzia nanchuanensis'' (Ching & H.S.Kung) Ching & H.S.Kung
*'' Huperzia nanlingensis'' Shrestha, F.W.Xing, X.P.Qi, Y.H.Yan & X.C.Zhang
*'' Huperzia occidentalis'' (Clute) Kartesz & Gandhi
*'' Huperzia petrovii'' Sipliv.
*'' Huperzia porophila'' (F.E.Lloyd & Underw.) Holub
*'' Huperzia quasipolytrichoides'' (Hayata) Ching
*'' Huperzia rubicaulis'' S.K.Wu & X.Cheng
*'' Huperzia rubricaulis'' (Alderw.) Holub
*'' Huperzia saururoides'' (Bory & D'Urv.) Rothm.
*'' Huperzia selago'' (L.) Bernh. (including ''H. selago'' subsp. ''appressa'' - Appalachian firmoss)
*''Huperzia serrata'' (Thunb.) Trevis.
*'' Huperzia shresthae'' Fraser-Jenk.
*'' Huperzia somae'' (Hayata) Ching
*'' Huperzia sprengeri'' (Nessel) Holub
*'' Huperzia suberecta'' (Lowe) Tardieu
*'' Huperzia sumatrana'' (Alderw.) Holub
*'' Huperzia sutchueniana'' (Herter) Ching
*'' Huperzia tibetica'' (Ching) Ching
*'' Huperzia yakusimensis'' (Herter) Holub
*'' Huperzia zollingeri'' (Herter) Holub

Former species

Many species formerly placed in ''Huperzia'' have been transferred to the genus ''Phlegmariurus'', including the following (synonyms from ''World Ferns''):

*''Huperzia ascendens'' = '' Phlegmariurus ascendens''
*''Huperzia austroecuadorica'' B.Øllg. = '' Phlegmariurus austroecuadoricus''
*''Huperzia columnaris'' B.Øllg. = '' Phlegmariurus columnaris''
*''Huperzia compacta'' (Hook.) Trevis = '' Phlegmariurus compactus''
*''Huperzia crassa'' (Humb. & Bonpl. ex Willd.) Rothm. = '' Phlegmariurus crassus''
*''Huperzia cumingii'' (Nessel) Holub = '' Phlegmariurus cumingii''
*''Huperzia espinosana'' B.Øllg. = '' Phlegmariurus espinosanus''
*''Huperzia hastata'' B.Øllg. = '' Phlegmariurus hastatus''
*''Huperzia llanganatensis'' B.Øllg. = '' Phlegmariurus llanganatensis''
*''Huperzia loxensis'' B.Øllg. = '' Phlegmariurus loxensis''
*''Huperzia mannii'' (Hillebr.) Holub = '' Phlegmariurus mannii''
*''Huperzia megastachya'' (Baker) Tardieu = '' Phlegmariurus megastachyus''
*''Huperzia nutans'' (Brack.) Rothm. = '' Phlegmariurus nutans'' – (oahu, kauai)
*''Huperzia phlegmaria'' (L.) Rothm. = '' Phlegmariurus phlegmaria''
*''Huperzia polydactyla'' B.Øllg. = '' Phlegmariurus polydactylus''
*''Huperzia scabrida'' B.Øllg. = '' Phlegmariurus scabridus''
*''Huperzia talpiphila'' B.Øllg. = '' Phlegmariurus talpiphilus''
*''Huperzia varia'' (R.Br.) Trevis. = '' Phlegmariurus varius''

Distribution and habitat

As circumscribed in the PPG I classification, ''Huperzia'' is distributed in temperate, arctic and alpine habitats, including mountains in tropical Asia. Its species are terrestrial or grow on rocks. ''Phlegmariurus'' is epiphytic, and has a worldwide tropical distribution, so when ''Huperzia'' is defined broadly to include all three genera of the subfamily Huperzioideae, it has an almost worldwide distribution, absent mainly in North Africa, the Arabian Peninsula and Western Asia.

References

External links

Picture gallery

{{Taxonbar, from=Q2111150

Lycophyte genera